Mixing apparatus

ABSTRACT

The invention relates to apparatus for dispensing granular material, for example plastics granules dosed with a coloring agent. Granular material and the coloring agent are located in supply hoppers and metering means feed predetermined metered quantities to a mixing device which supplies the dosed material to a supply hopper. The apparatus is arranged to operate when the level of dosed material in the supply hopper falls below a predetermined level, whereupon actuation of the metering means causes automatic replenishment to that level.

United States Patent Brooks June 3, 1975 MIXING APPARATUS 2,458,692 1/1949 Downer 259/DIG. 20

4 9 J [75] Inventor: Frank Brooks, Atherton, England 2 3/195 ones 259mm 20 [73] Assignee: Foscolor Limited, Lancashire, Primary Examiner-Robert Jenkins England Attorney, Agent, or FirmCaesar, Rivise, Bernstein & 22 Filed: Oct. 16, 1973 when PP 407.032 57 ABSTRACT The invention relates to apparatus for dispensing gran- [30] Foreign Application Priority Data ular material, for example plastics granules dosed with Oct. 16. 1972 United Kingdom 47664/72 a eolerihg egeht- Granular material and the eelerihs agent are located in supply hoppers and metering 52 us c1 259/16; 259/3 means feed predetermined metered quantities to a 51] int. Cl B0lf 9/08 mixing deviee which pp the dosed material 19 a [58] Field of Search 259/25, DIG. 2o, 14, 15, pp y hepper- The pp s 18 e s to Operate 259/16, 30, 31, 32, 57, 53 32 84 35 3 when the level of dosed material in the supply hopper falls below a predetermined level, whereupon actua- [56] Refere Cit d tion of the metering means causes automatic replen- UNITED STATES PATENTS Shmem have" 780,757 1/1905 Lockwood 259/58 5 Claims, 6 Dr Figures SHEET v3 MOTOR DRIVE MFA/VS SHAFT GEARS FIG. 5A

1 MIXING APPARATUS The invention relates to mixing of materials, for example, proportioning of a small quantity of one material into a proportioned major quantity of one or more other materials.

It is an object of the invention to provide apparatus for such mixing which apparatus is of relatively cheap construction and which will have a relatively long maintenance free working life.

According to the invention, there is provided:

an apparatus for delivering to a receiver a mixture in predetermined proportions of particulate materials, comprising:

a source of each of the materials;

a mixing device;

metering means adapted at each actuation thereof to feed a measured quantity of each material from the respective source to the mixing device;

the mixing device comprising a cylinder and a rotary mixer blade therein, the cylinder having an opening in its wall and being rotatable about its axis between a first position in which the opening is disposed to receive the measured quantities of materials from the metering means and a second position in which the opening is disposed to deliver the materials to the receiver;

and drive means for actuating the metering means,

for moving the cylinder of the mixing device from its first to its second position, and for rotating the mixer blade during such movement.

The invention is illustrated by the accompanying diagrammatic drawings in which:

FIG. 1 is a sectional elevation of one form of apparatus in accordance with the invention;

FIG. 2 shows in two alternative operating positions part of the apparatus shown in FIG. 1;

FIGS. 3 and 4 show parts of the apparatus of FIG. 1 in different positions of operation; and

FIG. 5, comprising 5A and 5B, are top and side views, respectively, of the drive means.

The apparatus of FIG. 1 includes two side-by-side supply hoppers l, constituting sources of two particualte materials. A metering device is located below each hopper 1, and comprises a rotary cylinder 2 and associated stator flanges 3 and is connected via rotating shafts (FIG. 5) to drive means for the apparatus. Each cylinder has an opening 4 in its wall and the opening communicates with a measuring chamber 5. Preferably at least one of the chambers 5 is of adjustable volume; conveniently by means of an adjustable screw 6, as shown for the left hand chamber.

A mixer 7 is mounted below the metering devices. The mixer comprises a stationary cylindrical housing 8 in which fits a rotatable cylinder 9. The housing 8 is formed with openings and flanges which define an inlet 10 and an outlet 11. The cylinder 9 has a longitudinal slot in its wall and a rotary mixing blade 12 is mounted coaxially on a rotatable shaft (FIG. 5) in the drive means within it.

The drive means is a conventional assembly including a motor and gears for rotating drive shafts and the components connected thereto.

A receiver 13 is mounted below the mixer 7 and is connected to the inlet 14 of an injection molding machine 15.

The reciever 13 is mounted on a fulcrum 16 (FIG. 2), so that it can pivot between the two positions A and B shown in FIG. 2. The receiver is so asymmetrically shaped about the vertical plane through its pivot axis that it will tip from position A to position B when the level of the material therein falls sufficiently and will tip in the reverse direction when the level rises sufficiently. A microswitch 17, located in the path of movement of the receiver 13, is adapted to make or break a circuit controlling drive means for the metering devices and the mixer 7.

When the drive means (FIG. 5) are in operation the cylinders 2 are rotated so that during each revolution chambers 5 are first filled with materials by gravity flow from the respective hoppers 1 (FIG. I) and then dis charge such materials by gravity into the mixer 7 below (FIG. 3). Cylinder 9 is rotated synchronously with the cylinders 2 and is positioned with the slot therein uppermost when the material is discharged by the cylinder 2, so that the material directly enters the cylinder 9. During the subsequent part of the revolution the mixing blade 12 is rotated (at a speed faster than that of cylinder 9) so that by the time the slot is directed downwards (FIG. 4) the materials are adequately mixed. The mixed materials are then discharged by gravity into the receiver 13, from which the mixed materials flow into the inlet 14 of the injection molding machine 15.

When the receiver 13 contains more than a predetermined minimum quantity of the materials, it is in position A, so that the drive means are not energized and the metering devices and the mixer 7 are stationary; when the contents of the receiver fall to the predetermined minimum the changed position of the center of gravity causes the receiver 13 to move from position A to position B and this movement actuates the microswitch 17 to complete a circuit for energizing the drive means of the metering devices and the mixer 7. A fresh supply of premixed material is then delivered to the receiver 13 until the quantity of material therein rises to a predetermined maximum, whereupon the changed position of the center of gravity causes it to move from position B to position A and this actuates the microswitch 17 to break the circuit and de-energize the drive means.

In a preferred use, the materials are plastics powders and/or granules dosed with a coloring agent, the coloring agent being in one supply hopper and the plastics material in another.

Without further elaboration, the foregoing will so fully illustrate my invention that others may, by applying current or further knowledge, readily adapt the same for use under various conditions of service.

What is claimed as the invention is:

1. Apparatus for delivering to a receiver a mixture in predetermined proportions of particulate materials, comprising:

a source of each of the materials;

a mixing device;

metering means adapted at each actuation thereof to feed a measured quantity of each material from the respective source to the mixing device;

the mixing device comprising a cylinder and a rotary mixer blade therein, the cylinder having an opening in its wall and being rotatable about its axis between a first position in which the opening is disposed adjacent said metering means to receive the measured quantities of materials from the metering means and a second position in which the opening is disposed adjacent said receiver to deliver the materials thereto;

and drive means for actuating the metering means,

for moving the cylinder of the mixing device from its first to its second position, and for rotating the mixer blade during such movement.

2. Apparatus according to claim 1, in which the metering means comprises for each of the materials a cylinder having in its wall an opening communicating with a measuring chamber in the cylinder, the cylinder being rotatable about its axis between a position in which the opening is disposed to receive sufficient material from the respective source to fill the measuring chamber and a position in which the opening is positioned to deliver the material in the measuring chamber to the mixing device the drive means being effective to rotate the cylinders of the metering means and of the mixing device in synchronism with one another.

3. Apparatus according to claim 1, in which the parts are so disposed that the materials can flow by gravity from the sources to the metering means, thence to the mixing device and thence to the receiver.

4. Apparatus according to claim 1, including means for automatically energizing the drive means when the quantity of material in the receiver falls to a predetermined minimum and for automatically interrupting such energization when the said quantity to a predetermined maximum.

5. Apparatus according to claim 4, in which the receiver is mounted for tipping movement about a horizontal axis and is so asymmetrically shaped about the vertical plane through that axis that it will tip in one direction when the level of the material therein falls sufficiently and in the reverse direction when the level rises sufficiently, such tipping movements of the receiver being arranged to cause energization and deenergization respectively of the drive means. 

1. Apparatus for delivering to a receiver a mixture in predetermined proportions of particulate materials, comprising: a source of each of the materials; a mixing device; metering means adapted at each actuation thereof to feed a measured quantity of each material from the respective source to the mixing device; the mixing device comprising a cylinder and a rotary mixer blade therein, the cylinder having an opening in its wall and being rotatable about its axis between a first position in which the opening is disposed adjacent said metering means to receive the measured quantities of materials from the metering means and a second position in which the opening is disposed adjacent said receiver to deliver the materials thereto; and drive means for actuating the metering means, for moving the cylinder of the mixing device from its first to its second position, and for rotating the mixer blade during such movement.
 1. Apparatus for delivering to a receiver a mixture in predetermined proportions of particulate materials, comprising: a source of each of the materials; a mixing device; metering means adapted at each actuation thereof to feed a measured quantity of each material from the respective source to the mixing device; the mixing device comprising a cylinder and a rotary mixer blade therein, the cylinder having an opening in its wall and being rotatable about its axis between a first position in which the opening is disposed adjacent said metering means to receive the measured quantities of materials from the metering means and a second position in which the opening is disposed adjacent said receiver to deliver the materials thereto; and drive means for actuating the metering means, for moving the cylinder of the mixing device from its first to its second position, and for rotating the mixer blade during such movement.
 2. Apparatus according to claim 1, in which the metering means comprises for each of the materials a cylinder having in its wall an opening communicating with a measuring chamber in the cylinder, the cylindeR being rotatable about its axis between a position in which the opening is disposed to receive sufficient material from the respective source to fill the measuring chamber and a position in which the opening is positioned to deliver the material in the measuring chamber to the mixing device, the drive means being effective to rotate the cylinders of the metering means and of the mixing device in synchronism with one another.
 3. Apparatus according to claim 1, in which the parts are so disposed that the materials can flow by gravity from the sources to the metering means, thence to the mixing device and thence to the receiver.
 4. Apparatus according to claim 1, including means for automatically energizing the drive means when the quantity of material in the receiver falls to a predetermined minimum and for automatically interrupting such energization when the said quantity to a predetermined maximum. 